Signal distribution system



Sept. 18, 1951 P. M. G. TOULON SIGNAL DISTRIBUTION SYSTEM 4 Sheets-Sheet1 Filed April 6, 1949 INVENTOR PIERRE MARIE GABRIE L TOULON ATTORNEY p1951 P. M. G. TOULON 2,568,375

SIGNAL DISTRIBUTION SYSTEM Filed April 6, 1949 4 Sheets-Sheet 2 SYNCSEPARATO PIERRE MARIE GABRIEL TOULON ATTORNEY Sept. 18, 1951 P. M. s.TOULON ,3

SIGNAL DISTRIBUTION SYSTEM Filed April 6, 1949 4 Sheets-Sheet 5 m r'lSYNC- \q INVENT( R PIERRE MARIE GABRIEL TOULON BY /Zg ATTORNEY Sept. 18,1951 P. M. G. TOULON 2,558,375

SIGNAL DISTRIBUTION SYSTEM Filed April 6, 1949 4 Sheets-Sheet 4 77:GABRIEL TOULON ATTORNEY patented Sept. 18, i951 SIGNAL DISTRIBUTIONSYSTEM Pierre Marie Gabriel Toulon, Neuilly-sut-Sein,

France, assignor to Products & Licensing Corporatlon, New York, N. Y., acorporation of Delaware Application April 6, 1949, Serial No. 85,906

In France April 8, 1948 13 Claims. 1

'The present invention relates to a new process for creating on theterminals of a generator successive voltage impulses, whose duration andamplitude are exactly defined, and particularly impulses in trapeziumform. More particularly the invention relates to the creation of voltageimpulses which are necessary to assure static distribution, amongseveral independent channels, of signals which arrive sucessively by asingle lead.

I succeed in assuring this static distribution, by using rectifiers inparticular. For example, all the independent channels are fed inparallel by the common lead I install serially in each channel a valve,and I dispose, furthermore, a battery polarized in such a direction thatall the rectifiers are normally blocked. In series with each rectifier,I connect an inductance or a resistance in which (by means of aninductive coupling or by capacity) a voltage can be made to appear at agiven moment and for a brief duration. The inducted voltage is verycomplex; it is a peak voltage, constituted of superimposed voltages ofvarious frequencies. Its maximum is produced alternately in each one ofthe channels. The peak of voltage has the effect of compensating for thepolarization of the battery, and thereby of unblocking the rectifier.

Until now, a voltage presenting a very accentuated maximum at a givenmoment of the period has been used; that is to say the peak of a curvehas been used, having approximately the form of a sinusoid, whoseamplitude compensated the battery. In many cases, this approximatesolution can sufilce; but peaks in rounded form, considering the shapeof the curve from its peak as a function of time, is not verysatisfactory, especially when extremely precise operation is desired. Itvery often happens, then, that the signal subject to distribution is nottransmitted completely, if the system which assures the unblocking ofthe line is only approximate. This happens, for example, if the timingof arrival of the signal is not in rigorous synchronism with the timingof the peak of the complex curve, which compensates for the batteryvoltage; or, it can also happen (notably as an outcome of the variationsin the voltages of the network), that the amplitude of the complexvoltage which assures the unblocking of each line takes on differentvalues, and consequently the peak of voltage instead of being'exactlyequal to the value of the battery, is weaker or stronger than thelatter, that is to say, the amplitude of the maximum varies in thecourse of time. This defect is not grave, if the peak of voltage actsonly on the unblocking grid of an amplifying tube disposed in eachtrack, because the tube then exercises a saturating efiect, which is whysuch amplifying tubes have always been used in practice. But the defectbecomes absolutely prohibitive when utilizing, as the inventionproposes, simple rectifiers; nevertheless, this solution is thepreferable one, because it is the simplest and most economical. It is aprimary object of the present invention accordingly to render possiblethe use of rectifiers in systems of the above character.

According to the invention, instead of using directly the peak of thiscomplex voltage to unblock the switch rectifier of each track, I utilizeit only to create a fall in the voltage existing in resistances disposedserially across a rectifier,

which is itself disposed in such a way as to permit that current to passwhich the peak of voltage produces. The amplitude of the fall of volta eat the terminals of one of these resistances is limited by an auxiliaryrectifier appropriately polarized by a voltage practically equal to thatof an unblocking battery of the different tracks. The only purpose ofthe other resistance is to limit the current. I succeed in this way ingenerating voltage impulses having about the form of a trapezium, whoseamplitude is very exactly defined.

The pulses in trapezium form are utilized advantageously to measure therapid storing of signals in each one of a plurality of independentchannels. They can also be used for the discharge of these signals,after a predetermined time, and immediately before the arrival of a newsignal.

The accompanying drawings enable a better comprehension of the objects,features and advantages of the invention, and its mode of operation asexemplified in specific embodiments thereof.

Figure 1 illustrates, as a function of time, several superposed voltagepulses, corresponding to amplitudes of output of a generator, and whichare very different from each other in amplitude, and brings out therebythe fundamental role played by the limiting-rectifier of the presentinvention;

Figure? is a schematic diagram of a distributor which utilizes thetrapeze pulses, according to the invention;

Figure 2A is taken from Figure 2, and represents the principle of thevoltage limiter;

Figure 3 represents, on an enlarged scale, the curve of the trapezium;

Figures 6 and 7 are schematic partial circuit diagrams, taken fromFigure and l Figure 8 represents, as a function of time, the voltages inthe various parts of the diagram .of Figure 5.

All of these figures are providedas examples-- only, and without anyrestrictive or limiting intent as to the scope of the invention.

In Figure 1, there is illustrated voltage impulses I, 2 and 3, havingvery diiferentamplitudes. eral 4 represents, in cross-hatch, the veryprecise amplitude of the pulses which clipping vPermits one to obtain,according to the invention;

Reference is'nowmadeto'Figure'z ofrthe drawings, which figure is aschematic diagram pe mitting-switching successively into each one oftheindependentchannels Ii; 6, etc. (each one represented by a condenser6A shunted by a resistance 61 the signals which arrive successively viathe common lead 5. I install serially on each channel 6 a rectifier, as:I, 'I" and a voltage generator having the effect of blocking and ofunblocking alternately each rectifier I, l" I have designated by I theinput circuit, by which the useful signals and the synchronizing signalsarrive at the same time.

Element 9 has the effect of separating the usefulsignals on the commonlead 35, and'the synchronizing signals on lead III. In general'thesynchronizing signals are easy to separate, whether their direction ortheir amplitude diifer from the usefulsignals, or whetherthe times oftheir ocurrenc be fi r nt- By the aid of synchronizing pulses on lead,III, and according to a techni c describedby the present inventor inhis various patents, I interconnect one or more oscillators .(block II)whence .I derive by additive synthesis of several sinusoidal ase 9 t alica on. tog e i s 12, 1 em, complex voltage waves shifted in time'inrelation to One another.

The invention, illustrated in block 8, consists of transforming thevoltage impulses furnished at the terminals I2, and of an amplitudewhich maybe very irregular andof relatively high value, into impulsesofrelatively .feeb-le amplitude,and very exactly defined in amplitude, atthe terminals feeding the valves I, i"

"To arrive at thisresult, the invention provides across each pair ofterminals I2, two resistances I3 and I4, connected inseries, andtolimitthe drop in voltage in the resistance I4 by means of a valve I6appropriately polarized by a battery I5, and connected across resistanceI4. I utilize the voltage drop created across resistance I4 to feedvalve 1, which serves to accomplish switching to the first channel.

Figure 2A, taken from Figure 2, illustratesa circuit employing theprinciple of the voltage limiter; the same parts being designatedby thesame reference numerals. When the generator G feeds the resistances I3and I4 in series with the battery l5, the valve It prevents the drop involtage ,in the resistance M from going above the voltage of the batteryI5, which brings about thereby the limitation desired. As a matteroffact, as soon as the voltage at the terminals of On the other hand, thereference num- 4 the resistance I4 goes above that of the battery I5,the resultant voltage creates a current flow in the valve It, whichreduces the voltage at the terminals automatically to be equal to thatof the batteryIE.

The neighboring terminals I2, etc.,-are connected likewise in a group oftwo resistances I3, I4, etc. The drop in voltage in the resistances islikewise limited by a polarized valve I6. The operation of the system ofswitching is readily understandable. Assume first that all theterminals. I 2, I2, etc., of the generator I I do not deliver anycurrent. No drop in voltage i produced in the resistances I3, I4, I3,I4, etc., and, accordingly, all of the rectifiers I are blocked by thebattery 55.

The voltage in peak form, which appears at each terminal I2, passingacross the valve generates in the resistances. I3 and I4 a peakedcurrent. The drop of voltage created by this current in the resistanceI4 is limited by-the valve I 6. This difference in potential annulsmomentarily'the effect of the battery'I5, in suc'h a-way that'the firstsignal is switched'toward channel l. It being assumed that the dropofvoltage inthe resistance I4 corresponds very-exactly-to the value ofthe'battery I5, compensation is perfect.

The advance'presented by the present invention will be betterappreciatedbyreference to Figure '3, which represents as a function oftime, the form of thevoltage impulses utilized in-the prior art, ascompared with that which the system of the present invention permitsoneto obtain. I

The method described in my previous patents, to assure distributionamong several independent channels of signals arriving successively by asingle channel, consists of generating polyphased tensions, atfrequencies KlF,K2F,'Whi-Ch are different multiplesof the frequencyF ofthe recurrence of the signals in each channel, in such a way as tosynthesize peaks of voltage, which-are utilized in each of the channelsin'series with-a rectifier.-

In Figure 3, -I-have represented-at I6, as afun'ction ofgtime, theamplitude of the voltage at-the frequencyFiassumin-g K1=-l) and in IIthe fre quency KzF, (assuming K2=5). I have represented at I il-th'esumof thesetwo voltages, which constitute one ofthecomplex voltages -ofthe generator, presenting a very accentuated maxi-- mum I9.This-complex'voltage has been used in the past for u-nblocking' thefirst channel; I have represented by'dotted-lines another complex curve,I8, having the same formas the preceding one, and presenting;-a t I9, -avery-accentuated maximum, which'is utilized to unblock the secondchannel. The 'curve- It, with its peak I9", is formed; in thesame-manner as-the curve I'll-,- with its peak I9, by com-biningproperlyphased sinusoidal volta ges, of selected frequencies.- The relat'ivetime displ'acements-of pealgsI9- and l9- are accomplished bysuitableselection'of phases of the componentsinusoidal waves; I haveutilized; in the past, a polarizing battery; Whose ampli tude, shown "inE,- corresponds about to that of the maxima 19, I9, in such-a-waythat-the induced complex voltage; almost-compensatesfor thebattery-voltage at the moments of these maxima. This 1 arrangementpresented "certain difficulties; *the rectifierhaving the function'ofunblocking each channel is submitted to avery high inverse voltage,(equal-to 'twicethe "amplitude, E) with attendant danger of breakdown.Thebattery incircuit with the current generator, which furnishes thevoltage E; must be very stable.

For the same reason, the elementary voltages- (in phase and inquadrature), which serve to Finally, if the signals which aresynthesized are not perfectly synchronized withthe maxima I! of thecomplex wave, that is to say, if they present any relative advance ordelay, the unblocking is not correct, because the induced voltagesremain then, in either case, below that of the polarization voltage E.

All of these defects are avoided by' generating, in conformity with thepresent invention, an unblocking pulse having an exactly definedamplitude H, and in the form of a trapezium. In Figure 3, I haverepresented at MUVN the pulse which the system of Figure 2 enables oneto obtain; I obtain it also with the arrangement of Figure 4, wherein isagain found the fundamental elements already described in connectionwith Figure 2. The upper part of the schematic diagram of Figure 4treats of the operation of storing the impulses in each condenser (6A)associated with each line, and the lower treats of the discharge.

l.Storing.-In this Figure 4, I have designated by I the transmissionchannel, over which the useful signals and the synchronizing signalsarrive at the same time.

I have represented by block 9 the circuits which separate thesynchronizing pulses into lead I 0, and the useful signals into thecommon lead 5. I also propose to distribute the signals which arrivesuccessively over lead 5 among the independent leads 6, 6, etc. I havedesignated as block G components which generate peaked voltages bysynthesis.

As in the usual technique, I use an oscillator 20 synchronized inresponse to signals arriving over lead It] at the frequency of thepulses in each lead (frequency F). This generator drives severaloscillators 2|, 2|, etc., at the frequencies KIF, K2F, respectively,which are harmonics of the fundamental frequency F.

Beginning with these oscillators, I generate at each frequency, voltagesin windings 22, 23, 22', 23, respectively, in phase and in quadrature.Each one of these windings serves to impress on the terminals TD of thegenerator, by additive synthesis, the complex voltages having a verysharp maximum, at a given moment of the period F. These voltages areobtained by couplings of appropriate signal amplitudes present on thecoils 22, 23, 22, 23. This technique has already been described inFrench Patent No. .P. V. 552,650 (March 30, 1948), having the title: NewGenerator of Complex Electric Tensions, Intended Notably for theDistribution of Impulses. We have represented by T1, D1, the first ofthese complex tensions obtained by means of the couplings 221, 2-31,22'1, 23'1, having appropriate values. I obtain at T2, D2, the second ofthese complex voltages obtained from the windings 222, 232, 22'2, 232,by suitable choice of intercoupling values. The choice of the couplingvalues (notably the number of turns of the transformer)- enablesdetermination of the "phase" at the maximum of the complex voltagegenerated in each channel, as already explained in the patent cited.

In the present diagram, terminals T1, T2, etc., are available on oneside, terminals D1, D2 on the other. I connect to terminal D1, a groupof two resistances S1 and W1 in series with the terminal T1. Likewisethe resistances S2 and W: are connected in series with the terminal T2,etc. Each junction point of the group of two resistances, as S1, W1, orS2, W2, is tied to the cathode of a valve, as L1, L2 for limitingvoltage amplitude. The anode of this tube is appropriately polarized bya battery 15, of voltage B. On the other hand, the other terminal T1 istied to the anode of a valve V1. Likewise the terminal T2 of theneighboring complex voltage is tied to the anode of a valve V2.

The cathodes of thesevalves are polarized by a battery 24, with voltageP. The common lead F is connected to:

the negative pole of the battery [5. Each independent lead 6, 6', etc.(represented here by 'a' The resistances S, of Figure 4, perform thesame functions as the resistances l3 of Figure 2; the resistances W thesame role as the resistances H, the valves L the same role as the valves16, the battery B the same role as the battery l5.

The functioning of the device may be easily understood, by referringagain to Figure 3. As long as the voltage of one of the anodes of therectifier of peak rectifier V1 fails to attain the amplitude P, of thebattery 24, that is to say, as long as point M of curve [8 has not beenreached, no current (Fig. 3), is passed by the resistances S1, W1. Ihave represented by MN the amplitude P of the battery 24, at the pointwhere the rectifier V1 begins to pass current. If we admit that thevoltage drop in the rectifier V1 is negligible, and that the voltagesources are capable of delivering considerable current, the drop ofvoltage in the group of the two resistances S1 and W1 is represented, onan appropriate scale, by the curve M, l9, N. This drop,

in voltage may be decomposed into two parts, that which appears in theresistance W1, being that which is included between the horizontal MNand the curve I91. At the point U, that is L1 begins to pass current. Itlimits thereby in a very perfect manner the amplitude of the drop involtage in the resistance W, at the ordinate H comprised between thehorizontal line MN and the horizontal line UV. The drop in voltage inthe resistance S, about which we need not concern ourselves,corresponds, of course, always to the region between the horizontal lineUV and the peak of curve l9. When the complex voltage begins todecrease, there is a moment whenthe rectifier L1 ceases to conduct(point V). The fall in voltage in the resistance W1 is represented againby the distance between the horizontal line MN and the curve I 91, whilethe fall in voltage in the resistance S1 corresponds'to theverticaldistance between the curves I91 and I9. It is thus explained how thetrapezium with our" en er d s ha been hte ned- 1. 15 ra Qi Pu se i e peia l t. r-asset: m dlstributionofpulses. As has already been ingrectifier ,R. Normally, no voltage appears. in.

the resistance W, and all ofthe lines are, there:

fore, normallyblocked. The circuit arrangement,

has the effect of successively creating in each resistance W adrop involtage, precisely. equal andi opp osite to H, which compensates exactlythe voltt ageof battery B.

Discharge.To accomplish a rapid discharge of thecondenser Bat. the endof a predetermined time, asfshown in thelower part-of the Figs;

Ilutilize an auxiliary rectifier R, oriented in the reverse direction ofthe rectifier R and a polariz ing batteryB normally blocking therectifier R, and a generator of pulses for unblocking the rectifierperiodically.

As illustrated in Eigure 4, Iutilize an auxiliary generator G (which canbefed in parallel with the principal generator G). The generator Gutilizes symmetrical voltages derived, fromthe original generator G, butappropriately shifted intimein relation tothem. The generatorG', willinduce in the circuits D1, T1, D2, T21, complex voltages, eachpresenting a highly peaked maximum, at a predetermined moment. Due to;theresistances W"-1,S'1,W"2, S'z; and to the valves V1", V2 etc.,voltagepulses are vgenerated. These pulses. are in turn transformed intotrapezoids because of the valves L'1 L'2, and in accordance withthesprocess explained.above. The direction of ther trapezoid andthe timeof occurrence are chosen in such a way as to cause the valves R topasscurrent at the appropriate moment, that late say, immediately after thearrivalofanewimpulse in each line.

Figure 5.i1lustrates a variant of the system of Big. 4, iniwhich I usethe terminals of complex generator 6| to create alternately in eachresistance, T l trapezoidal voltage pulses which are alternatelypositive and negative, and which en-Q able successive storageanddischarge ofimpulses.

I have designated by'59 the line by which the useful signals and thesynchronizing signals anrive, and by 5-! the circuit which separates.the useful signals to line 53' and the synchronizing" signals to line 52The synchronizingpe'aks of complex voltage are generated-inblock 6]. The

generator 6| consists essentially, asha's been ex plained in the citedpatent, of a plurality of halfmonic oscillators 6L, 6I"", osci11atin gat therecurrence freouenciesof. the signals. After. amps,

fication, there is obtained. diphasedr distributions-J G2 .63, 62 ,63,etc., at each of the frequencies KiRKzE, etci I According to. theembodiment of my invention;- i1lustratedI'in-Figp5 of the-accompanyingdrawingaeach terminal ofthe generatorfii f-GBdS tVOj rectifiers at thesame time connected-in inverse parallel, or back-to-back. These'rectifiers are polarized,.respectively,:by batteries and 16,111

suchwa-way as to passcurrentonly at the peaks otvoltage. Thefirst-terminal of the generator; 61- feeds on one hand the cathodeofvalve 68;-

which passes current to the-resistance 55}; l on the other. hand,theanode of the valve 13 which passes currentto the resistance'lm Thevoltage pulsecreatedin this: resistance is passed-fby; am n ine en ci yl t-or r-h s; -va 'lf e-v arefed in in a group of two resi tamgesgnseries. 'Ijhe pos tiveandnegative voltage pulsesrare no t produ d 'i i efi lur k s v -h "uc'c'e'ssive terminals of the generatorgiil r er es ytquir rn h rqfis immer half or this. numb'eiaminus one l i by he, eme iei ie meral?! ii? ith 2? ihe e ements corr s nsiie al; Thus usefulvoltagesare piclseci' 've aegsaeea by; 10 a; 1 23, the condensers cohhsteers the tern-roars of next higher rank,

According to the invention, Iconn'ect together corresponding terminalsof condensers 'l 0 I and 1 2i, and-I connect the eor inected terminalsto resistances H and 51, which are in series: I proe ed in similar"manner fdrtfi elem'e tsbr t e ollow ing terminals, i e. uniteterminalsor-condensers 1c 'and 1 2 andc'onnect them to resistances J lam 5 catheter-1h series; etc

The positive and negative: maximum a'rnibli-Q tude's of the. voltageulsesin the resistance 51- are limited to an exactly deterrn'inedvajlue', the accordingtothe-principal object of the present inventionand explained" 'hereinbefo're} by valves!!! and 80, respectively,polarized by b'at terie's'it' and" 6B: The" common l'ine 53' feeds thecond'n'sers fl'; 5 3 corresponding to the diiferent independentchannels, each one" across a valve 55, 55,- etc, and thepolarizingbatterylifi nor mallyblocks ealrvalve; The drop in voltage in;

the resistance 51, disposed in series; has-the ef-: fect of unblockingthechannel-momentarily and permits the storing of thesignal in thecondenser 54 I utilize the voltage at the terminals of the condenser"54- to feed the transformer 528; of the first output channel A1. Thetransform-' ers 58, 58' assures isolation of D. C; voltages andenablesmatching ofimpedances. identical arrangement is utilized for the" othertracks, the same circuit components bear ing-the-same referencenumerals, followed by' an accent (output channel A2; condenser 5A, transformersaz-vaive 55 etc.). I

To assure-the :ra pid discha'rgeof the condenser 54", I utilize-anothervalve 59; whichis'normally' blqckedbythe battery 6!]. The negativetrape= zoidal pulse'vvhich appears across-the resistance 51 has: theeffect of discharging the condenser 54. The same arrangementis adoptedfor the, conden'ers' ofthe other channels 54', 54' etc.

Figures 6 and"? aresimplified circuit diagrams, taken, from'aFigure' 5;Eigure'fiwontainsonly the charging circuits at thefs'janie moment, butare shiftejd by A per o of. thecompleigvoltage which tI selct tobesirll;

60). "we must consider he e especially, r t follow s,,the terminal whoserank corresponds to e ies earne s n 1a of the rank 9 or-29, for example.

of the-:1condenser:- 514; and affords comprehension of the process ofdischarging condenser 54, immediately before the arrival of a new pulse,which enables prolongation of the action of the pulse in the channel. InFigures 6 and 7 I have designated the same parts by the same referencenumerals.

The functioning of the device is readily understood by reference tothese two figures. At the moment when (see Figure 6, storing) the firstimpulse arrives in channel 53, the complex volt age generator 64, 65,66, 61, passes its maximum output, and the valve 68 passes current toresist- I ance 69, generating a positive voltage pulse.

Dueto the capacitive coupling H! a positive voltage pulse appears at theterminal of theresistance 51, having the direction of the i signs inFigure 6. Due to the blocking rectifier 80, this voltage matches exactlythe voltage of battery 56. Valve 55 being oriented in such a way I as tobe able to pass current, the following signal in the input channel 53charges the condenser 54.

Immediately before the arrival of a new pulse in the input channel 53,the generator of complex-voltage 641,651, 861, 611, passes its negativemaximum, and the valve 131 passes current to the resistance 141 in theform of a negative voltage pulse. The capacitive coupling I01, havingthe same sign indicated on Figure 7, and the unblocking rectifier 19cause this tension exactly to balance out the battery 68. The valve 59being oriented in such a direction that it can pass current, thecondenser 54 is discharged.

Figure 8 represents the voltages which appear in the course of time inthe different portions of the schematic circuit diagram of Figure 5. Ihave represented on the first line 88 of this figure, in 8|, 82, 83,etc., BI, 82', 83, etc., the pulses which arrive successively via thecommon line 50. I have represented at 84, 84, the synchronizing pulses.They are, in the present example, of

opposite sign to that of the useful signals, which appears only theimpulse 8h, while all the other impulses which arrive by the commontrack before or after fail to attain the threshold of functioning of therectifier. The rectifier 55 has, therefore, the effect of storing in thecondenser 54 the signal of the first channel.

I have represented at 8 l2, the effect of the prolongation created bythe storing condenser 54.

On the following line of the drawing, I have represented at 89 thetrapezoidal pulse of negative sign appearing also on the same resistance51. This pulse is produced immediately before the arrival of a newpulse, in response to suitable choice of couplings picked in generator 6I, as will be seen by the curves at the bottom of the figure.

I have represented in reverse direction, in 891, this same pulse tofacilitate explanation, which is justified by the fact that the valvesare oriented in the reverse direction.

On the following line, I have reproduced again, at 852, the signal whichhas been stocked in the condenser 54. The effect of the impulse 89'1add- When the voltage becomes positive on valve 59, that is to say whenthe curve passes the horizontal line 60 corresponding to the voltage ofthe battery 60, the condenser discharges. I have represented thisdischarge by a shaded curve on the drawing, as a very rapid asymptoticdecrease.

To obtain successively the trapezoidal pulses of opposite sign 85 and89, which are necessary to discharge the condenser 54, and to storethereafter the pulse in the condenser, I utilize the complex voltageresulting from the superposition of several frequencies. In Figure 8, Ihave chosen as harmonics 3, 5, and 9, while in Figure 5, I had onlyrepresented thesynthesis of two voltages;

but the principle stays the same.

The complex curve '98 presents alternately a positive peak 18 andnegative peak 11. These peaks surpass the levels 9| and 92 at which arefixed the amplitudes of the batteries 15 and Hi. I have shaded the partof the pulses of voltage which are utilized. Figure 3 has permitted usto understand how the trapezoidal pulse 85 can be obtained, beginningwith the pulse 18. An analogous process permits obtaining thetrapezoidal pulses of negative sign.

In Figure 8, I have represented at 90, 90', etc., the complex curvesfeeding the successive terminals of the generator 6!. In the examplechosen, distribution is required between 20 independent tracks, and thebreadth of the peak has consequently been accordingly chosen. I haverepresented at 901 the voltage feeding the 9th terminal; in 99'1 thatwhich feeds the tenth terminals, etc- The peak I11 permits obtaining thenegative impulse 89 described above.

For the following channel82, I utilize the positive peak 18 and thenegative peak "'1, which enables storing and discharging, as has alreadybeen described.

The same complex voltage generator can be utilized to feed severalseparated distributors, each one controlling a common channel andseveral independent ones. This process is particularlyrecommended in thecase of a distribution in cascade, where the blocking rectifier enablesscope of this invention.

Having described my invention, what I claim I and desire to secure byLetters Patent is:

1. In a signal distribution system, means for generating a series oftimed displaced switching pulses extending from zero value to apredetermined maximum value, means for removing from said pulse thatportion thereof extending from zero value to a further predeterminedvalue, to provide a pulse peak, means for clipping said pulse peak toprovide a substantially square pulse having its base at said firstpredetermined ing to this signal, provides the shaded curve. tionsystem, means for generating a series of time egseegsas ping-said-peaksto obtain switching-signals-ofpredetermined magnitude, means forsuperposing 5' said: switching signals on -"saidinformation bearingsignals, and a normally closed channel for said signals opened only inresponse tosuperposed -switching signals and information bearing signalstogaccept said information bearing each of said switching signals, meansf0r-sep- -si'gnals. arating said *periodic peaks from said-switching"3,111 a system for distributing signals, occur- V ring in succession,to successive channels, means "for generating sinusoidal switching pulsefor mon bias-=voltage-. source-'for biasing an "or saidrectifiersagainst passage of -si'gnalsof less-than a predeterminedmagnitude, all ofsaid signals having maximum amplitudes of lessthan saidpredetermined magnitude, means for'generating switchingsignals-by-synthesis-of sinusoidal-*waves of harmonically relatedfrequencies; each of said switching signals having periodic peaks ofgreater amplitude than the remainder-'of said signals and'forclippingsaid periodiepea'ks-when separated to provide square switchingpulses of said predetermined amplitude, and means'ior said, channelsfinsuccession, means for app y g applying said switching"pulsesfor-unbiasingsaid said signals to said channels simultaneously, means.for'deriying from'said switching pulses :square. pulses of predeterminedamplitude, a

biased, rectifier blocking each. of said channels,

rectifiersin-timedsuccession,

8: In a system for distributing signals'occur- 'ring on asingle line toa "plurality of channels,

in timedsuccessiom'a difierent switching rectisaidbiased rectifierbiased by a steady voltage of goffier 'normally blocking each of saidchannels; a

said; predetermined; amplitudaandmeans for applying saidflsguarfifPulses to unblock said rectifiersi n e iqn.

4. 'In a systemfor 'distributingsignals occurring in successiontosuccessive channel's, means .for generating a, sinusoidal switchingpulse for each of said channels, said switching pulses occurring in time'succession, a circuit for each switching pulse comprising a biasedrectified" for passing only the peak of .said'switching pulse-- themagni u f he. .1 5 of, sai fur her biased gg rectifier, still, a furtherbiased rectifier in each .oiisaid channels. biased forpassing signals inexcess of said magnitude only, saidsignals'havinghmagnitudes lessthamsaid, magnitude, and I meansfor applyingsaidsignalsto said channelsg simultaneously.

5. In. a systemgfordistributing signals occurring on a single line ,to a.plurality. of channels in ,itimed succession, a switching. rectifiernor- ,mally blocking/each "of, said channels. and roe- 5 .sponsiveatoaeswitching pulseof predetermined amplitude I for unblock-mg .each, of,said .channels for passing signal thereto, meansfor generating aidswitching, pulses comprising means, for. gencom-mon biassourceforbiasing all of-said rec- =tifiers-to the=same voltageandagainst passageof signals of magnitude lessthan said voltage,

means for generating a switchingslgnal for each of said channels, inmutually'displacedtiinein- 't'ervals; each of said switchingsignals-comprising-an arcuate peak of amplitude greater than 'said'voltage, means comprising rectifiers biased by acommon voltage sourcefor derivingfsaid peaks'of amplitude, each in a separate-switch-'ingchannel, means for clipping each of said peaksof amplitude "to' formsquare" pulses-of a common-'- value equal to'said voltage, and-means Yfor apply ng said square j-pulseseach" to unbi'as one of said first'mentioned rectifiers; ain a system 'for distributing signals occurringon a single line to a plurality of condensers I and; forthereafter"discharging each of said condensersat predetermined intervalsafter charge thereof by one of said signa'ls; comprising'a 'difierentbiased" switching rectifierfor'normallyblocking each of said condensersagainst said-signals,

means for applying' said signals jointly=to* said rectifiers' forpassage to said I condensers, a common voltage source for applyingidentical" bias to all said'biased'switchin'g=rectifiers, means-forgenerating a switching musesof identical amplitude to unbias' saidrectifiers' in timed succession and in synchronism with saidsi'gnals,and' further erati ng, switching, signals by synthesis from. 8,1-switchingrectifiers'shunting said condensers'and plurality of sinewaves; and meansiorclipping the peaks and the. bases ;ofsaid switching.signals :to derive said;switch-ing:pulses;of said predeter- .-minedamplitude,

6.4 In a-. system for distributing signals. occur-- ring on a singleline; to a, plurality-.- of channels,

in timed succession, a difierent switching rectifier normally-blockingeach-.of'said channels, a common biasvoltage source .forrbiasing all ofsaid rectifiers against voltagaofalesssthan a predeter- -sgo minedmagnitude, said-signalsall having-amplitudes,v less than said apredetermined magnitude, means .for generating-switching signals bysynthesis. of sinusoidal swayes a of harmonically related :frequencies;'meanssfor deriving from each' 55 .01. said-switching; signalsapltrapezoidal switching 'pulse of said predetermined amplitude, andmeans forapplyingsaid switching: pulses to unbias said; rectifiers'initimedsuccession to enable :passage 'ofsaid signals to said;channelsrintimed '1 succession.

'7; :In: asystemsfor distributing-signals occurring on a single line toa plurality ofrchannelsfln timed succession, 2a: different switching:rectifier normally blocking eachi of said 'rectiflers, a com-: i 7

pole'd for discharging sai'd' condensers but having a biasfor preventingsuch discharge, and means "for overcoming'said last named'b'ia's at'eachof said further switching rectiflers to dischargeieach of saidcondensers at said predetermined interval after charge thereof.

10. The combination in accordance withclaim 9 wherein saidnrieanssizorgeneratingswitching pulses comprises means forsynthesizing'wave .10 wherein said means for overcoming said last'namedibias at eachiof'said further switching rectifiers icomprises:said means for synthesizing wavesh'apes and meansfor-deriving peaksonly of.;said wave shapes :of polarityopposite to said one polarity, andmeans for clipping said last mentioned peakstto" derive trapezoidalpulses, and -zmeans-=for*applying ."said trapezoidal pulses to "saidfurther switching. rectifiers,

,12. Aisystemior charging and di'schargingi a condenser at timedintervals in accordance with the amplitude of a signal, comprising, acontrol lead for said condenser, means for applying alternate positiveand negative voltages to said control lead, a fixed bias rectifier meansnormally blocking said condenser against charge in response to saidsignal, means for connecting said control lead to said rectifier forapplying said positive voltage precisely to overcome said fixed bias.whereby said condenser is charged in accordance with the amplitude ofsaid signal, and a further fixed bias rectifier for controllingdischarge of said condenser, said control lead connected to apply saidnegative voltage to overcome bias of said further fixed bias rectifierto discharge said condenser.

13. In a system for charging and discharging a condenser at controlledtimes, a source of charging current for said condenser, biased rectifiermeans normally blocking said condenser with respect to charging fromsaid source, further biased rectifier means normally blocking saidcondenser with respect to discharge of charge accumulated thereby, asingle control line, means for applying alternately positive andnegative pulses to said control line, means responsive to saidpositivepulses applied to said control line for unbiasing said firstmentioned rectifier means to unblock said condenser with respect tocharging, and means responsive to said negative pulse for unbiasing saidfurther biased rectifier for unblocking said condenser with respect todischarge thereof.

PIERRE MARIE GABRIEL TOULON.

REFERENCES CITED The following references are of record in the file ofthis patent:

